[Cystic neoformations of the retroperitoneal space (4 case reports)].

Based on the study of four cases of retroperitoneal cysts, the complex histopathogenesis of these neoplasms - the clinical diagnosis of which has recorded substantial progress thanks to the use of the computed tomography - has been analyzed. The practice of exeresis, though comparatively simple and radical in most cases (as recorded in 3 out of the 4 cases reported) owing to the little adhesions of these neoplasms to the contiguous anatomical formations and also to their histological benignity, may, in some instances, present such unexpected difficulties due to the expansion in volume and the complex and delicate anatomical connections, that palliative operations have to be opted for.